In my U.S. Pat. No. 4,817,994, entitled "Aseptic Pipe Joint," issued Apr. 4, 1989, and U.S. Pat. No. 5,076,617, entitled "Seal for Aseptic Fitting Assembly," issued Dec. 31, 1991, seal ring assemblies are shown and described for aseptic processing systems. These seal assemblies have particular application in the processing of foods and other products such as pharmaceuticals which require careful handling and appropriate precautions to provide sanitary equipment and thereby prevent contamination of the product. The seal-type assembly in the '994 patent is used to provide a seal in the ferrules of the pipe joints. This type of seal assembly, because of its circular configuration, does not provide a continuation of the internal surface of the pipe joint which would result in small trappings and build up of product in the joint.
The aseptic seal ring assembly described in the '617 patent uses a seal in the form of a U-shaped metallic ring filled with a resilient material such as rubber. The ring includes an enlarged flange on the end of each of the legs of the rings which are deformed to provide a metallic seal between the flanges of the pipe joint and the U-shaped rings. In this regard the U-shaped ring is provided with radial surfaces which are rotated into alignment with the radial surfaces of the pipe joint forming a metal-to-metal seal between the ring and the ferrule. This requires precise alignment in order to achieve metal-to-metal contact between the flanges.